At USC, my impression of FR is that unless you're one of a few select "hot ticket" PNMs (in which case all the power is in your hands), the balance of power lies overwhelmingly with the sororities. Few women have a full schedule, much less one with all the houses they wanted, for every round of recruitment.

I think your perception is skewed since I highly doubt you've seen every PNMs invite list. This stuff functions like a bell curve. The chapters and PNMs both fall on that curve in relation to recruiting power. The chapters rarely get every PNM they want for every party, either. It's recruitment. You pick up and move on with what you have.